My 'go to' route planner for all my journeys, never (with one exception - but EVERY other route planner/sat nav gets it wrong too! - A non-applicable width restriction on the best route confuses them!) been sent a duff way by it. Tweak the dimension figures to perfectly match your caravan if you want (it's set to my van), but it's unlikely to change the routes offered.
Like many others on here, I’ve driven these roads (in a short MH). Absolutely not a problem, even if you have a huge TA caravan.
Take A90 north from Forfar: it’s a good fast road, nothing steep, much of it is dual carriageway, as you’ll know when you’ve driven to Forfar.
Keep on this A90 to pass Stonehaven. When you get to the new Aberdeen bypass (still dual carriageway), take the A96 to head inland - probably signed to Huntly, where there’s a CAMC affiliated site. Keep going on this A road until you get close to the coast, then head east on the A98 until you’re near Findochty: then just follow local road signs.
Enjoy your trip.
The OP might want to re-read the advice they were given when they asked (at this time last year) about getting from Forfar to Greenwood loch caravan park.
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